Fruits, leaves, bark, nuts, seeds, insects, and honey.
The Sumatran orangutan (P. abelii) is more frugivorous and insectivorous and eats less inner bark of trees than do Bornean orangutans (P. pygmaeus) (Wich et al. 2004)
More than 500 plant species recognized in diet of orangs
They have been described as "gardeners of the forest" for the role in seed distribution (Rijksen & Meijaard 1999)
Eating soil is not uncommon in the wild.
Very rarely observed eating small vertebrates (birds, lizards, rodents, slow loris).
Time spent foraging on different types of food varies greatly season to season.
When fruits are scarce, orangutans spend up to 90% of their foraging time eating shoots and leaves.
Water obtained mostly from the vegetation eaten; also by licking wet vegetation and fur on forelimbs.
Often exhibit bimodal pattern of foraging (morning and afternoon), separated by periods of rest.